In present technology solution, MDT (Minimization Drive Test) is divided into Immediate MDT and Logged MDT based on reporting mode:
Immediate MDT, the terminal equipment performs MDT measurements and report in connection state; the terminal equipment will immediately report the measurement results to eNB (evolved Node B)/RNC (Radio Network Controller) in form of multiplexing RRM (Radio Resource Management) once the conditions are met.
Logged MDT, terminal equipment collects measurement results in idle state, which will be reported in subsequent connection state. Terminal equipment will log the measurements results and report those to eNB/RNC at proper opportunity subsequently.
Log configuration of MDT is sent to terminal equipment with a new configuration message, which is not based on current RRM measurement mechanism.
Terminal equipment side: terminal equipment will not release Log configuration received when releasing RRC (Radio Resource Control) connection, but will keep configuration and launch Log task and measurement results collection in idle state.
Network side: network will not keep MDT context information for Logged MDT, nor transfer MDT context among network unit. When RRC connection is released, MDT context saved at network side will also be released at the same time.
In Logged MDT mode, when terminal equipment saves valid MDT Log and enters connection state from idle state, it will report Log available to network via. RRC signalling to inform the network side that the terminal equipment saves available MDT Log.
LTE (Long Term Evolution) system is taken as an example to explain. RRC connection setup procedure is shown in FIG. 1. After the successful setup of RRC connection, terminal equipment sends to network the RRCConnectionSetupComplete message that carries the indication information on whether terminal equipment saves available MDT Log (viz. said Log available). After receiving the indication, network can request subsequently terminal equipment to report the MDT Log saved.
Similarly, during cell handover and reestablishment procedures of LTE system, terminal equipment will send Log available information to eNB of target cell switched/reestablished cell to inform the new cell whether available MDT Log is saved in terminal equipment.
In UMTS (Universal Mobile Telecommunications System), if SRNS (Serving Radio Network Subsystem) relocation process occurs, terminal equipment will also send Log available message to target cell.
Terminal equipment may be reconfigured with Logged MDT task when moving to a new cell; then it will delete the Logged MDT configuration saved previously and MDT results having not been reported yet; while terminal equipment will save the original configuration and Log results if it does not receive new Logged MDT configuration when moving to a new cell.
As shown in FIG. 2, several OMC will be provided in a network at present to maintain different eNBs respectively. Typically, if an operator adopts equipment of different manufacturers for networking in a province of China, every manufacturer will have its own OMC (Operations &amp; Maintenance Center) to maintain its equipment. If no interface is set up between OMCs of different manufacturers, it will be impossible for MDT data to be transferred among OMCs.
Similarly, as shown in FIG. 3, a network may have several PLMNs (Public Land Mobile-communication Network). The network may be shared, such as operator 1 shares the same network with operator 2, operator 1 maintains PLMN1 and operator 2 maintains PLMN2. When both the two operators do not sign a contract regarding mutual transmission of MDT data, it will also be impossible for MDT results to be transmitted between different PLMNs.
In the course of implementing the present invention, the inventor finds out there are at least the problems below in the present technology:
When Log information is available for MDT in terminal equipment, it can be informed to network side through RRC message during setup/handover/reestablishment/cell update procedures and trigger network side to acquire Log information in terminal equipment. With the handover procedure, reestablishment procedure, or cell update procedure, the updated cell and the original cell may belong to different OMCs or PLMNs. If terminal equipment sends the same Log available indication to target network side, the target network may request terminal equipment to report MDT Log. However, if network side does not support the reporting across OMC or PLMN, radio resource will be wasted. Furthermore, terminal equipment will delete corresponding MDT Log after reporting it, which will cause the loss of MDT Log.